Identifying and ageing of injuries

An artefact in forensic pathology is something imitating disease or injury occurring in life. Discovering and recording all the disease and present in the deceased is one of the aims of the autopsy. So things which look like disease or injury but are not and they’ve simply been introduced in some way or other after death are a huge danger. Artefacts are many and varied. A simple example is CPR, cardio-pulmonary resuscitation, compression of the chest is part of trying to resuscitate someone. Rib fractures occur very often, even in well performed CPR. Untrained people actually tend to be too gentle with cardio-pulmonary resuscitation.

And you can imagine the forensic problem in some cases, in that it can be impossible to unravel whether these rib fractures were there before the CPR started and therefore, part of an alleged assault or whether they were the result of the resuscitation or could each have caused some of them. The sources of possible artefact can be summarized as follows. Interference with the body during the process of dying, and we’ve talked about cardio-pulmonary resuscitation, but also intubation, intravenous access. Post-mortem injury by the assailant. Now, injuries after death are technically not part of the assault. Post-mortem injury by body handlers. Occasionally the body is dropped. Embalming artefacts. Insects, land and aquatic animals. The effects of things like fire or water.

Post-mortem changes themselves. Lividity would mistaken, sometimes as bruising. These can mimic general signs of neck compression with haemorrhages in the eyes, intestinal ischaemia ,effects of gastric fluids. Putrefaction interferes with identification, causes skin slippage misinterpreted as heat damage. Discoloration, misinterpreted as bruising. Dilatation of orifices misinterpreted as penetration. Conducting the autopsy itself. Reflection of the scalp, dissection of the neck prior to brain removal, laryngeal fractures caused during removal of the neck structures, skull fracture caused when removing the calvarium. All of these additional artefacts.

To deal with this briefly, we need to contend again with an effect, as we’ve discussed. We need to understand that bruises may require dissection to be identified. There’s a forensic truism, just because you can’t see a bruise on the outside doesn’t mean there aren’t bruises on the inside. The corollary of that is you need to go looking for bruises in relevant cases, and that means dissection. Minor injuries tend to be overlooked, but are important for understanding the larger picture. For example, the abrasion on front of a wrist, in a hanging in custody, might be very persuasive for a family about self-inflicted injury. Aging injuries is imprecise.

Fresh injuries with no sign of healing at all occurred at or around the time of death. But in the case of bruises, this might extend back to 24 hours before death. In other words, forensic pathologist generally cannot tell the difference, and nor can anyone else, between a bruise inflicted five minute before death and one inflicted 12 to 24 hours before death. Bruises in color, but this has defeated researchers as a tool for timing injuries because of the variability of colour change purple, blue, green, brown, yellow, the order that colour change and its timing. Despite this, it’s very common to hear forensic pathologist ageing bruises.

The only evidence based statement about the age of a bruise is, if you can see a yellowing, it is more than 18 hours following infliction. There’s no published evidence to show that forensic doctors can age injuries reliably, either as an individual or as a group. When the claim is made the forensic doctor should be challenged to provide the evidence basis for two things. What’s the evidence that such ageing can be done reliably? And secondly, please demonstrate that you personally are able to do this reliably by producing evidence of participation in a quality assurance exercise or something similar testing the aging of injuries.